Fuse



June 23, 1925. 1,543,232

c. H. PEARSON ET AL FUSE Filed Oct. 25, 1920 Patented June 23, 1925.

UNITED STATES PATEN T 1 CHARLES H. PEARSON, 0F BROOKLINE, AND FREDERICKw. 301.15, or anemia, Messa- CHUSETTS; SAID BOLD ASSIGNGR TO SAID LPEARSON,

FUSE.

Application filed October 25, 1920. Serial No. 41 $),3'2i, i

To all whom it may concern: 7

Be it known that We, CHARLES H. PEAR- soN, a citizen of the UnitedStates, and resident of Brookline, in the county of Norfolk and State ofMassachusetts, and FREDERICK W. Bow, a citizen of the United States, andresident of Chelsea, in the county of Suffolk and State ofMassachusetts, have invented an Improvement in Fuses, of whichthe'following description, in connection with the accompanying drawings,is a specification, like letters on the drawings representing likeparts. Our present invention relates tomechanical time fuses, and moreparticularly to me:- chanical time fuses adapted to be applied toordnance shells for the purpose of det0 nating the charge therein aftera prede: termined length of time following theldis; charge of the shellfrom a gun. In fuses of this character, wheratheop; crating parts arenecessarily of delicatelcqns struction and are subject to the ,sh ekgsrtremendous forces, such operating jp ar ts must not only be of reliableconstruction, but. must be associated \vithand-surroundedi safeguards toensurepositive-safetylito the operating parts, the shell to whichi suchl parts may be, attached, and particularly to the operators who must'handle themz S0. manydi fl'erent things may: happenfto .a fuse, underso many-different oonditionsvthat the prevention of accidents hasactually become a prime objectof .inventorsi of-this class iifdevicesThe most frequent cause of: accidents has been the premature explosionof the shell charge-by any accidental releaseofthefiring pin "because ofshock or other, reason-T cans-v. ing the-detonation of the primerrof thefuse and the resultant dischargeof the shell charge.Inthepriorapplication of Fred.- erick NV. Bold, Ser. No. 334,849, filed-Oct-l 31, 1919, an important safety device was d'ee vised, consisting ina shutter,.eithersliding or -pivoted, between the primer and the firing:pin, las a positive interposed member, .and', we have now still further-improvedQthis, safety shutter utilizing-it, or any sirnila ri movable'member, .to vnormally flhold theprimer out of firing positionyand, bythe' firing of the gun, to automatically position itinto firingpositionw7H .Q ,One of the principal objectsofour invention, therefore, is toproyide safeguards against accidental, explosions, One of these safetyelementsis agnovl means for ,c'a'rry'a ing the primer, (and. (normallyretaining. it;

wholly out ofialinement with thefiring pin, and also entirely removedIfroinzand practically closing ,thegpassage leading to ,tlie deto-lnating chamberl Ourfiii'venti'o i thu's'.. ,per-f mits thefluseiof. highexplosives with j greater safety than} has be'en possible 'p'rior' tothis invention. Preferably, we employ means.'.to hold the primer. out'of.firinglposition until sii ch meansfli's, ,mdv'ed jin'to position: by:Nthe centrifugalfiforces generated by, the rotation offlthe 1 'sh'ellon. ,i'tsi discharge, from a; gun, when thepigirner; is automatically.positioned and 'ie ady 'for the release of the, firing pinfourteen-.itl'iousand: times, and. that the cen-,

trifngal force .set by the rotation 'of the shellis such that at adistance of iap proxi matelyfive eightli s' of an (inch from. the axisof the fuse suchcentrifugal Q force is approximately equal to the forcedue to v the shock of; firing, l\."ot .v ithstanding the tremendousforces set up by the shock of firing and the rotation of the shell, themoving parts of atiming meohanismshouldrun very accurately, foriwiththegreat velocity ofa shell wheniina flight, anyerror in the runningtimeof the-fuse maymake a .tre

Inendous difference .in the results f obtained. I

The, carrying, .orlwhat may be termed the stati naryL arts of the fuse,.must .be, there,

fore, ,.o.f such rigidv construction as -to be lmDIIH-IBIIfIOHI;the-effects of all :shocks and centrifugal, force, :while the (moving-elements,,such aspthe, time train andv escape ment, niustjbe light inweight so as to run freely. and; without binding, as .must alsothe-firing pin and release mechanism there'- for; One of -the mostimportant moving elements is the setting-disc, plate or wheel,

that cooperates withj'the setting cap" or head to set the timingmechanism and with the firing mechanism to release the firing pin atthe-proper instant. Such setting disc should be light in weight, becauseit is carried on and rotated by the time train and yet should be rigidenough to prevent chattering or vibration when subjected to shock. Weattain these results by making suchsetting disc in the form of aCOIICa"O-COIIVQX OI dished whee'l,' and preferably a s'poked'wheel tosave weight. beveled c'ut 'away portion in the rim cooperates with aspring pressed latch to connect the same temporarily. with acorrespondingly beveled partcar'ried by the setting cap t head and toand surely seat together;

Another object of our invention therefore, is an improved' formofsetting disc for fuses of this character.

In our present improved construction, the connection between the settingdisc and the setting'cap is's'uch' that the setting disc. haspractically no zero position; that is, the setting disc may be movedinto such a position that the firing pin release lever is in alignmentwith the notch in the setting disc, but such notch is filled by theconnesting means from the settin cap and,

therefore, there is no danger of premature explosion from this cause.This construction has several advantages, one of which is the feature ofbeing able to set the disk from either side of the zero point. For

" example, assuming the setting cap to be resting in such a position onthe base as to indicate that the setting disc is in zero position. Informer construction, if it were necessary, say, to set the disc torelease at 75, the setting cap must necessarily have been rotatedthrough practically a complete circle. This is not so in our presentdevice where, assuming the setting disc and setting cap to be in theposition above noted, if it is desired to set the mechanism to bereleased at 7 5,. the setting cap is merely rotated through acomparatively small angleto ring the mark into position to set the disc.I

The setting disc is mounted on the staff ofth'ev time train, andheretofore considerable difliculty has been experienced because of theseeming impossibility of obtaining suitable and positive connectionbetween such disc and staff. Where a circular conmotion between the twoelements was relied upon, too close fitting was necessary to avoidobjectionable back lash. Where a tapered connection was relied upon,relative movement between the two elements was so likely to'occur thatdoubt always existed as to whether or not the fuse was properly timed.We have overcome these objections by providing a non-circular connectionwith the tapered connection-,with the result that automatically theobjections enumerated aboveare eliminated.

Still another object of our invention, therefore, is an improved form ofconnection between the setting disc and center staff of the timingtrain.

An important element of the constructio;-. of this fuse is theconnection between the setting cap or head and the setting disc. Thisconnection must be a positive one in order that the fuse ma be properlyset and yet Inust be capable of being positively broken by the shock offiring. We may also utilize the centrifugal force to aid in breakingsuch connection, if for any reason the same should be delayed, and aftersuch disconnection,- the el' nmactin member, in addition to being heldout hy the spring hereinafter referred to, is positivelv held andmaintained out of the way of the disc by the centrifugal force due tocontinued rotation of the shell. A further object of our invention,therefore, is an improved form of connect-ion between thetetting cap orhead and the setting disc.

In the prior application of Frederick W. Bold, Ser. No. 334,849, filedOctober 31. 1919', the spring ringlocated between the settingcap or headandjthe base of the fuse has been provi'ded with V-shaped depressions inwhich the pointed ends of adjusting screws fitted, and by means of whichscrews'the't-ension of the spring was ad justed. Such a construction wasunsatisfactory in some fuses, because under certain severe conditionsthe 'V-shaped depressions and screw. holes in cap became deformed,rendering it impossible to properly tension said spring. [To overcomethis difficulty is a still further object of our invention wherein Weprovide an improved form of adjusting means for adjusting the tensionbetween the setting cap or head and the base of the fuse. The shock dueto firing the shell from the gun is a source of failure of the timingapparatus to operate, due to the end of the driving spring of the saidtiming apparatus becoming disconnected from the winding gear. Thereforeanother object of our invention is an improved means for connecting theend of the driving spring ofthe timing apparatus to the winding' gear toprevent accidental disconnection.

Afurther object of our invention is an improved" form of winding andtesting means for the driving springs of fuses of this character,permitting the spring to be wound or tested from either end of thefusebase, and when wound or tested from the lower end, this can be done withthe cap in place.

In our present invention the primer is located in a rotatable platepreferably operable by centrifugal force, and normally out of alinementwith the passage leading to the detonating chamber. In order that theholding plate or shutter cannot be moved into position to aline saidprimer with said detonating chamber, we have provided a positive lockingmeans therefor to be released or unlocked by the shock of firing theshell from a gun.

A further object of our invention, therefore, is improved safety devicesfor the rotatable plate or shutter, or the like means which ispositioned between the firing pin and the charge.

As an additional safety feature, independent of all others and one thatis of great importance, we so arrange the timing movement on. the fusebase that when the neu tral or safety' point on the setting cap is setat the neutral or safety point on the base and with the firing pincontrol lever then in the pathway of the setting lever engaged in theslot in disc, it will be impossible for the firing pin to be released.

Other objects and novel features of construction and arrangementof'parts will appear as the description of the invent-ion progresses.

In the accompanying drawings, illustrating a preferred embodiment of ourinvention,

Fig. 1 is a sectional elevation;

Fig. 2 is a sectional plan view, taken on the line 22 of Fig. 1:

Fig. 3 is a sectional plan view, taken on the line 3-3 of Fig. 1;

Fig. 4 is a fragmentary sectional view, taken on the line 44 of Fig. 3;

Fig. 5 is an enlarged detail of a portion of the setting disc;

Figs. 6 and 7 are detail views of the hub portion of the setting discillustrating the method used to prevent rotation of said disc on thestaff, and also showing; the shoulder on said stafi to prevent any setback movement of said disc on said staff on shock of firing;

Fig. 8 is a detail view of a lock for connecting the setting cap andsetting disc together;

Fig. 9 is an enlarged detail view of the primer carrying plate orshutter;

Figs. 10 and 11 are detail views illustrating our improved means forattaching a driving spring to the winding gear;

Fig. 12 is a detail sectional view of the gear Winding pinion. with themeans for operating the same from the bottom or top of the movement:

F ig. 13 is a detail showing the improved means for tensioning thespring ring located between the setting cap and fuse base: and

Fig. 14 is an enlarged view of the plate or shutter stop pin.

Referring to the drawing, 10 designates a fuse base, provided withexterior threads 11 by means of which it may be attached to a shell, andwith a detonating chamber 12 on its lower end, this chamber being closedby the screw plate or plug 13 of usual. construction. A passage 14extends from the detonating chamber 12 to a depression 15 located in theupper portion of the fuse base 10. The upper face of the fuse base isrecessed at 17 to receive the lower plate 18 of the clock or timingmovement 19. Screws 20 hold the movement firmly in position in suchrecess, a dowel pin 21 in the lower face of the recess cooperating witha hole, (not'shown) in the bottom plate of the movement 19 to positionsuch movement.

Pivotally mounted in the depression 15 is a segmental plate or shutter22 provided with a recess or chamber 23 in which fits a primer 24. Thissegmental plate or shutter is cut away or reduced in thickness at theportion 25 to provide for the proper balancing of the shutter, while aradialslot 26 is provided at a side remote from the reduced portion 25.Intermediate the ends of the radial slot is a beveled hole 27 in whichis placed a stop pin 28, shown enlarged in Fig. 14,this stop pin looselyfitting in a hole 29 the fuse base 10 and under normal conditionsholding the segmental plate or shutter in the position shown in Fig. 3,with the primer 24 out of alinement with the passage 14. A stop pin 30embedded in the lower face of the depression 15 prevents anti-clockwisemovement of the segmental plate or shutter 22 should, for any reason,the stop pin 28 become disengaged from the beveled hole 27, while thesecond stop pin 31 likewise embedded in the lower face of the depressionlimits the clockwise movement of said segmental plate or shutter 22. Aspring 32 fastened at one end by the screw 33 lies parallel to the lowerface of the depression 15, extending between the stop pin 30 and thesegmental plate or shutter 22. with its free end in engagement with thesaid segmental plate or shutter, as clearly shown in Fig. 3, tending tohold such shutter in the normal or inoperative position. Located inalinement with the primer 24 and leading to the outside of the fuse base10, is a vent 34 preferably closed on its outer end by a screw or plug(not shown) suitable to keep out dirt and dampness, but capable of beingreadily blown out by the primer should it prematurely be discharged andthus affording a free vent and ensuring safety to the charge in theshell. This construction provides positive safety means for the fuse, asexcept under conditions that can never be brought about unt l the shellto which the fuse is attached is discharged from a gun, the primercannot be brought &

into alinement with the passage leading 'to the explosive chamber, anduntil such time the plate or shutter practically closes the passage 14leading to chamber 12.

The clock or timing movement 19 comprises the bottom plate 18, middleplate and top plate 36, spaced apart from each other by a plurality ofpillars,-37 and 38. being shown in thedrawing, and the cover plate 39is'secured to the top plate 36. The center staff 40 is mounted inbearings in the middle plate 35 and cover plate 39, and e.- tends abovesaid cover plate. The extreme end of the staff is threaded at 41 toreceive a nut 42, while the portion below the threaded portion 41 andabove the cover plate 39 is tapered, as clearly shown in Fig. -7.- Inaddition to being tapered, this latter portion is milled on oppositesides, andwith a shoul der thereon, as shown in Fig. 6, to provide apositive connection between said'sta-fi' and the setting disc 43,preventing the hub of said disc from being moved by either the shock'offiring or centrifugal force. "This setting disc 43 is cup-shaped, asshown in Fig. 1, to prevent vibration and chattering and therebyeliminate any possible derangement of the parts of the device due tosuch vibrations of the disc. Suchstiffen ing of the disc may-be by ribs,corrugations or equivalent reinforcements." To reduce weight as much aspossible,"the "setting disc 43 is made in the form of a-spoked wheel, asclearly shown in Fig.2, the rim'being-cut away at one point, as shown'in Fig. .5, the sides of this cut away portion being beveled at 44, forthe purpose to be hereinafter de scribed.

Fuses of this type are generally stored completely assembled, as shownin Fig. 1, with the driving spring 45 of the clock or timing movementwound up.

WVe have devised an improved means for winding the driving spring whichmay be operated from either the top or the bottom of the clock or timingmovements. The pinion 47 that meshes with the winding gear 48 i:- formedon or attached to a shaft 49, the upper and lower ends 50 and 51,respectively, are squared, as shown in Fig. 12. This shaft 49 is mountedwith its bearing in 36 and 39, being top and cover plates, respectively,39 being recessed in upper side to allow key to be inserted over square,and also cut away for the pinion 47. The set ting disc 43 is providedwith a perforation 52 through which the socket wrench or key may beinserted when it is desired to wind the spring 45 from the top of thetiming movement, while the fuse base 10 is provided with a hole 53 inalinement with suit able holes in the bottom and middle plates 18 and 35respectively, so that after the device is assembled and shipped to itsdestination, the mainspring may be Wound-.01

tested by removing the lug 13 and the screw -153 and inserting thesocket wrench or key-through the hole-53 in the fuse base 10 to engagethe lower portion 51. The headless screw 153 closes the hole 53 from thedetonating chamber; In testing the mainsprings in fuses of thischaracter and also on inspecting after'being fired in a protected ordummy shell, it has been found that some of the said springs becomeunhooked rendering them inoperative. To obviate this difiiculty andensure proper action of the device, we have devised an improved form ofattachment between the outer end of the driving spring and the windinggear. This attachment is illustrated in Figs. 10 and 11 andconsistsessentially of a stud 54 rive-ted in a hole in the annular wallof the winding gear 48, this stud being provided with a head 55 havingparallel sides perpendicular to the thickness of'the winding gear, thishead being parallel to and spaced-apart from the-annular 'wall of thewinding gear a distance slightly greater than the thickness of thespring 45, the outer end of which is provided with a slot 56 longer thanthe head of the stud and slightly wider than the width-of'the headbetween its parallel sides. To:assemble the winding gear and spring, theslot in the outer end of the spring-is slipped over the head of the"stud and the spring 45 is then rotated into position. The manner inwhich this is done will be obvious from an inspection of 'Fig. 10.

The upper outer portion of the fuse base 10 is cut away at 57 to providea bearing surface for the setting cap or head 46. On the Vertical faceof the cut away portion 57 is a groove, cut at right angles to said faceexcept that one edge of said groove is slightly beveled, in which grooveis placed a ring 58 of spring metal of the same shape and to fit saidgroove. This ring has holes or recesses in it to receive the reducedends of the screws 59, the shoulders of said screws to press against thefront of said ring to properly tension the cap and ring thereby enablingsetting and holding the cap in any desired position. A plurality ofheadless screws 59 are threaded through the cap 46 at various pointsabout the periphery of the cap. With this construction, there is notendency, as in prior constructions where a pointed screw engage-s21wedge shaped depression in the spring ring, to expand the screw hole inthe setting cap or head. By this device, also. the power required toturn the cap or head 46 during the setting operation, may be'varied tosuit any requirement.

()n the interior wall of the cap or head 46 is attached, in longitudinalgroove 62, by the screws 63, a plate 64 carrying spaced bearings 65 inwhich is pivotally mounted an irregular shaped member comprising a latch66 and cam 67. Also mounted in the bearings 65 is a curved spring 68,the outer free end of which engages with the cam member 67. Thisconstruction is clearly shown in Fig. 8, and it will be seen that withthe free end of the spring 68 in the position shown, that the latchmember 66 will be held to the right, and in engagement with the cut awayportion of the rim of the setting disc 43. The sides of the latch arebeveled to correspond with the bevel of the cut away portion of the saidrim and the tension of the spring 68 holds the said beveled end inengagement with said cut away portion, ensuring a connection between thesetting cap or head 46 and the setting disc 43.v When the shell, towhich the fuse is attached, is discharged from a gun, shock of firingcauses the irregular shaped members comprising the latch 66 and cam 67to be rotated on the bearing against the tension of spring, and movesthe beveled end of the latch out of engagement with the cut away portionof the rim of the setting disc or plate, in which position it will beheld by the free end of the spring bearing against the other surface ofthe cam than that shown in Fig. 8, and also by centrifugal force. Withth latch 66 in engagement with the cut away portion of the rim of thesetting disc 43, such disc may be rotated by means of the setting cap orhead to set the timing movement.

The operation is as follows, it being assumed that the fuse has beenproperly assem bled with the latch -66 in place at neutral point and thprimer in place. Before the bursting charge is put into the chamber 12and in order that the parts of the device may be disturbed as little aspossible, the operator or inspector, in order to ascertain if theoperating spring of the clock or timing movement is wound up, removesthe plug 13 from the bottom of the fuse base, and the screw 153 from thehole or passageway 53, inserts a socket wrench or key through thepassage 53 into engagement with the lower end of the winding shaft 51and tests the condition of the operating spring. Assuming that suchspring is found to be wound up, or if not it is then wound up, the screw153 is replaced in hole 53, the bursting charge loaded into the chamber12 and the plug 13 screwed into the bottom of the base. The fuse base isthen screwed into the nose or upper part of a shell. Vhen the fuse isabout to be fired, the operator rotates the setting cap or head 46 toset the cut away portion of the rim of the setting disc 43 at.

the point where it is desired to release the firing mechanism associatedwith the clock or timing movement. As above pointed out, the setting ofthe fuse may take place from either side of the zero mark on the settingcap. If now, the shell, with fuse attached, is placed in a gun and thegun discharged, the shock of firing does several things; the

clock or timing movement is started in operation by the release of latch66 from the disc, and the sliding sleeve 128 is removed from its leverholding the timing movement from rotation, as explained in said priorapplication of Frederick W. Bold, the extension 69 of the release lever70 slides on the moving periphery of the setting disc 43; the pin 28 inthe wedge shaped hole 27 in the cover plate or shutter 22 is pulled outof said hole and falls into and is wedged in the hole 29 in the fusebase 10, the beveled end of the latch 66 moves to the left upon thebearing 65 as viewed in Figs. 1 and 8, out ofthe cut away portion in therim of the setting disc, and the free end of the spring 68 engages withthe other face of the'cam 67 to hold the said beveled end permanentlyout of such cut away portion; all of'the above things happen practicallysimultaneously and as the shell starts to rotate at the instant ofdischarge, because of the rifling of the gun, the following may be saidto happen simultaneously with the above: The cover plate or shutter 22is rotated by centrifugal force in clock-wise direction to bring theprimer 24 into alinement with the passage 14 leading to the chamber 12,the setting disc'43 will be rotated by the clock or timing movementuntil the cut-away portion of the rim comes into alinement with theextension 69 of the release lever 7 O, the tension of the spring 71 issufficient to cause, by means of the collar 72 and beveled trigger 73,the rotation of the shaft 74, and the release and operation of thefiring pin 75, resulting in exploding, in regular order, the primer, thebursting charge in chamber 12 and the shell charge.

From the above, it is obvious that until after the shock of firing andalso until the shell is set in rotation by the rifling of the gun, anduntil the centrifugal force generated by such rotation is equal to orgreater than a certain predetermined amount, it will be impossible todetonate the charge of the shell, and even not then unless the settingcap has been moved away from its normal neutral location.

When the setting cap is at neutral, or zero position, it will be notedby reference to Fig. 5, that the extension 69 of the release lever 70 isin alinement with the latch 66. It is obvious, therefore, that if thefuse is subjected to shock sufficient to start the timing train inoperation, no damage can result as the latch 66 prevents the release ofthe firing pin. This is true even though the fuse be attached to a shelland fired from a gun, as neither the shock of firing nor the centrifugalforce will be sufficient to move the latch 66 out of the path ofmovement of the extension 69. In order for the device to operate,therefore, it is necessary for the setting cap to be first moved fromits neutral or zero position.

JAE th t na e lti ea ng #42 th chamber 12 ,is snitably filledwithpowder, ,pellets or the like, the plate or shutter-22 acts as protectingshield covering said assageway andalso acts as. a rsafety device for'preyenting' premature discharge of the .said powder, .pellets, or thelike,:by any premaftnre detpnationpi the primer 2e. Thi siadditionalsafety feature is --impor .tant char- V-acteristi of our invention.

As ourinvention relates to a type .of deviee; ,is intricate-incharacter, wveghave .necesear-ily deseribed the preierredembodiimentthereof somewhat in detail. :It ,is to be;unders t0od, however, that wemay vary the construetion and errangement'oftheelementeeonstituting-our;invention within considerably wide limitsWithout. depavting iron;thespiritthereof. 1 v

Alse ompinvention and certain features and rad vantagee can be utilizedin impact tuses-as ell as i-n timefuses, and therefore it i s to beunderstood-thateve intend such feat ures to be broadlyqcovered lbyg-theap- --e nd d la m r 1 Qur present invention-is i' urtherdescribed andgleiinedlin the ferm f olain sas follows: :In a time inse, the-combinationiof a baem a timing train mounted thereon, a firing pincontrolled in its operation {by zsaid :tlfll'lillg -trai n, -and .a.primer holding device, normally holding the primer out. of, the @pathpf kmovement of the rfiring pin, 7 means for iretaining thexsaid devicelnisaid position againet accident, said means ,being operable to releasethe .deviceion :the shock of :fil'iing, .said .device being operable Ibycentrifugal force to movetheiprimer into alinement with said firing:pin.

2. :In a time .fuse, the combination of a base, a timing train mountedthereon, a firing pin controlled inlits opera-tion by said timing train,.a primerholding device normally holding a .primer out of the path ofmovement of the firing pin, 'a safety pin detaohably connected to@saidvdevice and removable therefrom by the shock of firing to releasesaid device, said device being operable by centrifugal forcetomove theprimer into alineI-nent with said firing pin.

3. In a time fuse, the combination of a time'fusesetting disc,a beveledopening in the rim of said disc, a setting cap, means for connecting thesetting cap and :setting disc, having a beveled member fitting into saidbeveled opening and {lying flush with (the periphery of setting disc,and means I01; yieldinglysholding said member in contact with,theisideorrsides of vthe said openng. 4

In aitime fuse, the combination of a -base, a train mountedthereon, adriv- .ing spring for .said train, .and vmeans for winding :said drivingspring from both the top andvbottom of said base.

-5. In a time fuse, the combination of a base, a timing train mountedthereon, a driving ,spring for said train, a non-pen foratedsetting-cap, and .means for winding the driving spring with .said cap inposition.

:6. In a itirne iuse, the QOHlblIlitblQll Qf a base, a .timing trainmounted thereon, a dr ving vspring for said ,train, ,a ,tvinding e unnac e mw sp ae itha n 9P- 3r inl k y, e a in s aciated", ea id ztiming.tzrain, xi pinion on said shaft engaging with said windinggear, and aperforation in saidmase .in alinen'ient avith said 'gsllfhfit, wherebysaid spring may be :Wound the bottom of ,the .base.

.7. In combination with ,a petting plate ,puovided with-aradiallyextending SlOiJ tlltl .rotateble through an -nngle-of 360,, afiring ,pin releaseil ener adapted inovleiinto said s e endeeq ing fitiegr v i slot and normally ,pgreventing movement .of said leverintosaid slot. I,

I n im fine n at i legs n finge eni 'sm t n 'e fi l bg hyt 1- t n a plral ty e e 49 3 9- mziated with timingtrain and -.qp.erable by the effiring ant-l centrifiugal force to penmit dille detonatiqn Of the fuse,,in combination ,nzith connecting means; between the. setting cap ,and'timing train gfor ,posi- Zz'ively preventing operation ,o'f. the firingmechanism While said setting cap is in neutral position.

, 9.;In fcombination, vwith a setting plate provided with a radiallyextending slot and rotatable xin either direction on it s axis throughanangle orf .360?, ,a firing ,pin release adapted "toimove ,into saidslot, and a setting means Qfittingintosaid slot during the-:-setting,0peratiqn whereby the setting of the fuse gnay ,he .made(through the rotation of the .setting ,plate .in -either-direction. T

In testimony whereoij, we have [signed ,onr names to this specification.

H. ,PE AR$Q'N, FREDERICK W. BOLD

